iPhone connects and disconnects from Mac

Hy everyone.

I had same issue on my iphone 6, ios 9.3.2. After searching through the web i found following solution that helped me:

You need to reset your privacy and location info and then trust your iphone with itunes again.

1. Disconnect your iphone from cable.

2. On your iphone: ->Settings -> General -> Reset -> Reset Location & Privacy (accept all things).

3. Connect your iphone back to cable. (iphone will reconnecting again, don't worry, it will be soon over).

4. iTunes will ask about trust, accept all this.

After that your iphone should stop reconnecting repeatedly and start to charging normally.

I've also tried all this, too. Only way I can get it to connect is using the activity monitor workaround.

Plugging my 7plus into this mid 2015 retina Pro, and waiting for it to start its incessant beeping, then opening activity monitor and force quit usbd makes it connect.

but - it doesn't 'properly' connect. phone is charging, but doesn't show up in photos to import. which is what I wanted to to really.

Have you tried the activity monitor method? It’s quite tricky, but once you get the timing right it’s easy. Look for, and force end, the process called usbd one the phone is connected. It’s quite finniky as photos, iTunes and all sorts of other stuff pop up appear in the way of the activity monitor terminal but once it’s done it works.

Also on another note, your problem sounds a big deeper than the typical problem here.

Also try a higher charge. In the 90% range before plugging in.

Let me know.

I was having this exact issue and my brother and I tried ever troubleshooting thing you could think of and nothing would work. I finally tried again just for the sake of it after my phone was had charged up some and it now connects with no problem! When I was initially trying to connect my phone was close to dying and only had about 13% remaining, but after I got 50+% CHARGED no issues what so ever!

I HOPE THIS HELPS SOMEONE!!!

:)

This has happened to me so many times and I could never pinpoint the variables until this super helpful post! Thank you to all that have weighed in on this.

Here's what consistently works for me nowadays with my iphone7. If my phone is charged above 50% and my phone disconnects, then I need to delete the "usbd" process from the Activity Monitor on the receiving computer. If my phone is charged below 50% (and that battery indicator is not always that accurate), then charging my phone works. I did not realize that the power level on my phone would make a difference, but it does.

I also am having this issue when connecting both my iPad Mini 4 and iPhone XS, and killing the usbd process on my Macbook Pro also solves it.

But here's an unexpected twist: I only see the problem when using the lightning cables from those devices. If I use a lightning cable from my iPhone 6, it works fine every time, without having to kill the usbd process.

Can anyone else reproduce that? If so, maybe it's being caused by a characteristic of newer lightning cables?

Someone had this answer above but it wasn't explained well so like most of you I scrolled by. I tried in this thread and it didn't work. But this did! Open the Terminal app from Spotlight (Command+ Space) and enter the command sudo killall -STOP -c usbd

Yeah, it's that easy.

This will pause the usbd process. Now, connect the USB cable and check if the iPhone is still charging on and off rapidly.

I've had this problem for YEARS. I'm so glad it's fixed!

What worked for me; unplugging the cable from the Mac, plugged the cable into the phone first (iPhone 12), then plugged it back into the USB port on the computer, for whatever reason, that corrected it for me. Prior to this quick fix, it did not matter how many times I plugged my phone in, it would just show charging then not charging over and over.

I had the same issue. I found that if my phone is fully charged (don't know over which %), and I changed the settings in iTunes to NOT sync automatically, no more rapid disconnecting.

Try running the command below on your mac terminal every time you plug your iPhone in;

sudo killall -STOP -c usbd

Killing usbd in terminal worked for me.

Thank you so, so, so, so, much. I've been dealing with this issue for over a year. I appreciate it.

Try putting your phone into low power mode. That worked for me.

Never mind, rpmartins response using terminal solved it for me: https://discussions.apple.com/thread/8276949?answerId=33910238022#33910238022

For me it didn’t work . Updating OS solved as issue seemed to be with itunes

thanks

Ok I can also confirm that after doing ALL suggested fixes, the one that fixed it and allowed me to sync my photos was simply to have the phone charged up a lot (94% charge).

It sounds easy but its annoying to have to charge your phone at a wall socket, then sync photos as ideally I'd do them both simultaneously .

But hey, what do I know? I'm just a stupid iPhone & Mac customer who knows nothing........